Publications by authors named "Katherine Graham-O Regan"

A technically straightforward total synthesis of a new class of vancomycin analogues of reduced synthetic complexity was developed that provided tetrachlorovancomycin (, LLS = 15 steps, 15% overall yield) and its precursor aglycon (nearly 20% overall yield). The class retains all the intricate vancomycin structural features that contribute to its target binding affinity and selectivity, maintains the antimicrobial activity of vancomycin, and achieves the simplification by an unusual addition, not removal, of benign substituents to the core structure. The modification, accomplished by addition of two aryl chloride substituents to provide , permitted a streamlined total synthesis of the new glycopeptide antibiotic class by removing the challenges associated with CD and DE ring system atropisomer stereochemical control.

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Purpose: To evaluate the prognostic value of posttreatment fibrosis in human PDAC patients, and to compare a type I collagen targeted MRI probe, CM-101, to the standard contrast agent, Gd-DOTA, for their abilities to identify FOLFIRINOX-induced fibrosis in a murine model of PDAC.

Experimental Design: Ninety-three chemoradiation-treated human PDAC samples were stained for fibrosis and outcomes evaluated. For imaging, C57BL/6 and FVB mice were orthotopically implanted with PDAC cells and FOLFIRINOX was administered.

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An amplifiable magnetic resonance imaging (MRI) probe that combines the stability of the macrocyclic Gd-DOTAGA core with a peroxidase-reactive 5-hydroxytryptamide (5-HT) moiety is reported. The incubation of the complex under enzymatic oxidative conditions led to a 1.7-fold increase in at 1.

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Oxidized collagen, wherein lysine residues are converted to the aldehyde allysine, is a universal feature of fibrogenesis, i.e. actively progressive fibrosis.

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We examined a novel farnesoid X receptor agonist, EDP-305, for its antifibrotic effect in bile duct ligation (BDL) and choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) models of hepatic injury. We used molecular magnetic resonance imaging with the type 1 collagen-binding probe EP-3533 and the oxidized collagen-specific probe gadolinium hydrazide to noninvasively measure treatment response. BDL rats (n = 8 for each group) were treated with either low or high doses of EDP-305 starting on day 4 after BDL and were imaged on day 18.

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Syngeneic, immunocompetent allograft tumor models recapitulate important aspects of the tumor microenvironment and have short tumor latency with predictable growth kinetics, making them useful for trialing novel therapeutics. Here, we describe surgical techniques for orthotopic and heterotopic pancreatic ductal adenocarcinoma (PDAC) tumor implantation and characterize phenotypes based on implantation site.Mice (=8 per group) were implanted with 10 cells in the pancreas or flank.

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